ixgbe: fix LED blink logic to check for link

Previously the driver would force link without checking whether the link was
already established. This caused some inconsistencies in the LED blink rate.

Do not force link if link is already up.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c

@@ -751,16 +751,20 @@ static s32 ixgbe_blink_led_start_X540(struct ixgbe_hw *hw, u32 index)
 {
 	u32 macc_reg;
 	u32 ledctl_reg;
+	ixgbe_link_speed speed;
+	bool link_up;
 
 	/*
-	 * In order for the blink bit in the LED control register
-	 * to work, link and speed must be forced in the MAC. We
-	 * will reverse this when we stop the blinking.
+	 * Link should be up in order for the blink bit in the LED control
+	 * register to work. Force link and speed in the MAC if link is down.
+	 * This will be reversed when we stop the blinking.
 	 */
-	macc_reg = IXGBE_READ_REG(hw, IXGBE_MACC);
-	macc_reg |= IXGBE_MACC_FLU | IXGBE_MACC_FSV_10G | IXGBE_MACC_FS;
-	IXGBE_WRITE_REG(hw, IXGBE_MACC, macc_reg);
-
+	hw->mac.ops.check_link(hw, &speed, &link_up, false);
+	if (link_up == false) {
+		macc_reg = IXGBE_READ_REG(hw, IXGBE_MACC);
+		macc_reg |= IXGBE_MACC_FLU | IXGBE_MACC_FSV_10G | IXGBE_MACC_FS;
+		IXGBE_WRITE_REG(hw, IXGBE_MACC, macc_reg);
+	}
 	/* Set the LED to LINK_UP + BLINK. */
 	ledctl_reg = IXGBE_READ_REG(hw, IXGBE_LEDCTL);
 	ledctl_reg &= ~IXGBE_LED_MODE_MASK(index);